Describe how cholesterol is packaged after absorption in the intestine.

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Accepted Answer

All right. Hello everyone. So this question is a true or false, correct the statement if it is false after the absorption in the intestine, cholesterol is transported in its free form. So first what is cholesterol? Right? Well, cholesterol as the name implies is a sterile, which is a subgroup of the lipid family. So it's a type of lipid and because it's a lipid, right, by definition, it is going to be nonpolar. So it's important to have this context in mind when talking about how cholesterol would be transported in the blood. Now, speaking of blood, right? Because it's already been absorbed in the intestine, it is going to reach the bloodstream. And so blood, if you recall is mostly made of water and sits blood is mostly made of water because water is polar, it's not going to mix with our lipid with cholesterol. So cholesterol, at least as it is naturally in the free form is insoluble, which means that it's not going to mix well with blood. And if it can't mix well, it's not going to be transported very effectively. So if it's not soluble, it cannot be transported as well. And so what that means is that cholesterol has to be modified in some capacity so that it can be transported in the bloodstream. So here, right, we already know that the statement is going to be false because cholesterol as it is naturally cannot be transported in our polar blood, right, which is mostly made of water. So this is where lipoproteins come into play. Now, based on the name right, lipoproteins are a combination of both lipid and proteins. So now how does this help us solve our issue of cholesterol transport? Well, because lipoproteins are made of lipids and proteins. What that means is that lipoproteins have both nonpolar and polar regions. So in other words, right, a lipoprotein is able to interact with the aqueous environment of the blood while also being able to encapsulate the hydrophobic lipids and keep the lipids themselves inside of the protein away from the aqueous environment. And so it's through the use of these lipoproteins that the body can transport cholesterol through the bloodstream because the lipoprotein itself is soluble in water. And so the lipoprotein can hold essentially the cholesterol in the center away from the environment. So now what types of modifications are made to cholesterol? Well, first and foremost, cholesterol undergoes aeration verification results in cholesterol esters. And because of that ester functional group, what that does is actually make cholesterol even more hydrophobic than it was before. However, the reason why this modification is necessary is because the ester, the cholesterol ester can be packaged efficiently into the lipid core of the lipoprotein into the center of the lipoprotein away from the aqueous environment. This is because the esterified cholesterol is going to occupy less space. And if it occupies less space, what it does is allow for more cholesterol to be transported within one single lipoprotein. So what a stir application does just to summarize that and also write it down on the screen here is make cholesterol more hydrophobic but smaller, allowing for more of it to be transported at once. And so with that being said, we've arrived at our final answer, which I've prewritten on the screen here. So now I can show it. So the statement given here was false after the absorption in the intestine cholesterol is transported in its esterified form within lipoproteins. And so with that being said, thank you so very much for watching and I hope you found this helpful.

Describe how cholesterol is packaged after absorption in the intestine.

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Key Concepts

Cholesterol Absorption

Chylomicrons

Lipoprotein Metabolism